Ovarian function in the elephant: luteinizing hormone and progesterone cycles in African and Asian elephants

Serum samples were collected weekly for 3 yr from two female African elephants, for 18 mo from two other female African elephants, and for 2 yr from two female Asian elephants. Animals were not sedated at the time of blood collection. Ovarian cycles, characterized by changes in progesterone and immunoreactive luteinizing hormone (ILH) concentrations, averaged 15.9 +/- 0.6 wk (N = 25) for African females and 14.7 +/- 0.5 wk for Asian females (N = 10). The length of the active luteal phase averaged 10.0 +/- 0.3 wk for African elephants (range 8-14 wk) and 10.6 +/- 0.6 wk for Asian females (range 9-13 wk). Interluteal phases were 5.9 +/- 0.6 wk for African females and 4.2 +/- 0.5 wk for Asian females. One African female (Maliaca) had two extended interluteal phases, both occurring between the months of February and May. Excluding these two periods, there were no differences in the length of the ovarian cycle or the length of the luteal phase between species of elephant. Serum progesterone in both species ranged from less than 50 pg/ml to 933 pg/ml. Average progesterone concentrations during the luteal phase were significantly lower in African elephants compared with Asian elephants (328 +/- 13, N = 30 cycles vs. 456 +/- 23, N = 14 cycles; p less than 0.001). ILH ranged from nondetectable to 11.6 ng/ml. These data suggest that the length of the ovarian cycle in the African elephant is about 16 wk and confirm that the length of the ovarian cycle in the Asian elephant is about 15 wk.     

A new elephant fossil from the late Pleistocene of Alghero: The puzzling question of Sardinian dwarf elephants

Endemic elephants, variously reduced in size, have been reported from a number of Mediterranean islands. Most of these originated from the mainland species Palaeoloxodon antiquus. A few dwarf mammoth remains are recorded from Crete and Sardinia. In Sardinia, a largely incomplete skeleton and a few mammoth teeth have been reported from localities believed to range in age from the late middle to the late Pleistocene. The chronology of colonisation by the ancestral species, the actual persistence through time of Mammuthus lamarmorai on the island, and the morphological and dimensional range of the species are, however, poorly known. This research aims to describe a distal portion of a left tibia of a dwarf elephant found in the Alghero area (NW Sardinia), showing some morphological traits and dimensions consistent with those of the endemic Sardinian mammoth (Mammuthus lamarmorai). The main unanswered questions about chronology, colonisation and population dynamics of endemic Sardinian elephants are highlighted and briefly discussed.     

Social life of captive Asian elephants (Elephas maximus) in Southern India: implications for elephant welfare

Asian elephants in the wild live in complex social societies; in captivity, however, management often occurs in solitary conditions, especially at the temples and private places of India. To investigate the effect of social isolation, this study assessed the social group sizes and the presence of stereotypies among 140 captive Asian elephants managed in 3 captive systems (private, temple, and forest department) in Tamil Nadu, India, between 2003 and 2005. The majority of the facilities in the private (82%) and temple (95%) systems held a single elephant without opportunity for social interaction. The forest department managed the elephants in significantly larger groups than the private and temple systems. Among the 3 systems, the proportion of elephants with stereotypies was the highest in temple (49%) followed by private system (26%) and the forest department facility (6%); this correlates with the social isolation trend observed in the 3 systems and suggests a possible link between social isolation and abnormal elephant behavior separate from other environmental factors. The results of this study indicate it would be of greater benefit to elephant well being to keep the patchily distributed solitary temple and private elephants who are socially compatible and free from contagious diseases in small social groups at "common elephant houses" for socialization.     

Captive breeding and infant mortality in Asian elephants: A comparison between twenty western zoos and three eastern elephant centers

Poor reproductive success compromises the long-term viability of captive Asian elephant populations. A questionnaire was designed to assess the importance of reproductive behavior and husbandry factors on breeding success. This was circulated to a number of institutions, zoos, and circuses in Asia, Europe, and North America, all of which kept Asian elephants. The aims were to compare Asian elephant breeding success in different institutions, establish possible causes for any differences, and make recommendations for improving the welfare and breeding success of the animals. The results showed that breeding success in most of the zoos was notably lower and the percentages of stillbirths and infant mortality were relatively higher when compared with those of the institutions in Asia. Female elephants in zoos appeared to reach sexual maturity and reproduce earlier than those in the Asian establishments. However, zoo elephants produced fewer young per female. The different facilities and husbandry methods used are described. Recommendations are made for both short- and long-term changes that could be used to modify existing practices to improve the welfare and breeding success of captive Asian elephants. Zoo Biol 17:311–332, 1998. © 1998 Wiley-Liss, Inc.     

Indo-australian insular elephants

Various Pleistocene dwarfed elephants known from the islands of Celebes, Flores and Timor in the eastern part of the Malay Archipelago are described and their relationships considered. It is evident that these pygmy forms arose independently on each of the islands as a result of isolation and genetic drift favouring small size as in the better-known cases of the Mediterranean and Santa Barbara Channel Islands dwarf species. The dispersal possibilities of elephants are discussed; the conclusion must be drawn that geographic spacing has been the prime factor in species formation. Idle or fruitless speculations about ecological or other non-morphological species criteria have been omitted; the taxonomy of proboscideans as far as needed in the present context is however elucidated. It is pointed out that wherever we find pygmy elephants we have also giant rodents; in these presumably small isolated populations giganticism in small rodents appears to have been as advantageous to the animals as is dwarfing in elephants. As neither the exact date of colonization nor that of the eventual extinction (brought about by man or otherwise) is known, we have no means of knowing how many generations were involved; it is, however, likely that evolutionary velocity has been higher under these conditions than is usual.     

Obstetrics in elephants

Obstetrics, one of the oldest fields in veterinary medicine, is well described and practiced in domestic and exotic animals. However, when providing care during elephant birth or dystocia, veterinary intervention options differ greatly from any domestic species, and are far more limited due to the dimensions and specific anatomy of the elephant reproductive tract. In addition, aging of captive elephant populations and advanced age of primiparous females make active birth management increasingly important. Intrauterine infection, uterine inertia and urogenital tract pathologies are emerging as major causes for dystocia, often leading to foetal and dam death. This paper reviews the current knowledge on elephant birth and the factors associated with dystocia. It then summarises recommendations for birth and dystocia management. As Caesarean section, the most common ultima ratio in domestic animal obstetrics, is lethal and therefore not an option in the elephant, non-invasive medical treatment, induction of the Fergusson reflex or the conscious decision to leave a retained foetus until it is expelled voluntarily, are key elements in elephant obstetrics. Surgical strategies such as episiotomy and foetotomy are sometimes inevitable in order to try to save the life of the dam, however, these interventions result in chronic post-surgical complications or even fatal outcome. Limited reliable data on serum calcium concentrations, and pharmacokinetics and effect of exogenous oestrogen, oxytocin, and prostaglandins during birth provide the scope of future research, necessary to advance scientific knowledge on obstetrics in elephants.     

象科动物对当地森林生态系统的影响

现存的象科动物(Elephantidae)分为非洲草原象(Loxodonta africana)、非洲森林象(Loxodonta cyclotis)和亚洲象(Elephas maximus)3 种,作为森林生态系统的关键物种,它们对当地森林生态系统的影响非常复杂,在一定环境条件下,既可能是积极的作用,也可能是消极的作用。积极的作用包括:帮助植物传播种子;促进种子萌发;创造断层,维持群落多样性;为其他动物增加食物资源;为其他动物创造栖息地。消极的作用包括:使一些物种的种群数量减小;使森林变成灌木丛和草原等。而由于活动受限导致的种群密度过高是象科动物对森林生态系统产生消极作用的主要原因。当前象科动物的3 个物种均面临种群数量锐减和生存空间不断缩小的危机,为此迫切需要针对其对生物多样性和生态平衡的影响开展深入和全面的研究,并且应根据实际情况因地制宜地制定管理措施。     

Beehive fence deters crop-raiding elephants

Previous work has shown that African elephants Loxodonta africana will avoid African honeybees Apis mellifera scutellata . Here we present results from a pilot study conducted to evaluate the concept of using beehives to mitigate elephant crop depredation. In Laikipia, Kenya, we deployed a 90-m fence-line of nine inter-connected hives, all empty, on two exposed sides of a square two-acre farm that was experiencing high levels of elephant crop depredation. Compared with a nearby control farm of similar status and size, our experimental farm experienced fewer raids and consequently had higher productivity. Socioeconomic indicators suggest that not only was the concept of a beehive fence popular and desired by the community but also that it can pay for its construction costs through the sale of honey and bee products. We are calling for experiments testing this concept of a 'guardian beehive-fence' to be conducted rigorously and scientifically in as wide a range of agricultural settings as possible to evaluate jointly its effectiveness and efficiency.